When the National Interagency Fire Center released its 2013 wildfire outlook in early June, it did not forecast unusually high fire risk for Colorado. Most of the Rockies received some relief from drought during the spring, so there was hope that this year’s fire season would be more manageable than the last.

But then the heat arrived. Temperatures soared above 100°F (38 °C) in Denver on June 11, the earliest it has ever reached triple digits. That heat, along with gusty winds and drought-parched forests, came together to produce the Black Forest fire, the most destructive the state has ever seen. By the afternoon of June 13, the fire had destroyed 360 homes and damaged 14 others. The Waldo Canyon fire, Colorado’s most destructive prior to the Black Forest fire, destroyed 346 homes.

The Black Forest fire began on June 11 in a densely-wooded area north of Colorado Springs, Colorado. On June 12, 2013, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites captured these images of the fire about 20 miles (30 kilometers) northeast of Colorado Springs. The Terra image (top) was collected at 12:05 p.m. Mountain Daylight Time, and the Aqua image (lower) was collected at 1:40 p.m. MDT. Red outlines indicate hot spots where MODIS detected the unusually warm surface temperatures associated with fires.

According to firefighting agencies in Colorado, the Black Forest fire had spread through 15,000 acres (6,000 hectares) by the afternoon of June 13. Hundreds of people on the ground and numerous water-dropping helicopters and planes were fighting the blaze, but it remained zero percent contained on the afternoon of June 13. More than 38,000 people had been forced to evacuate their homes. Tens of thousands more people coped with elevated air pollution levels because of the fires.